This invention relates to a display method and apparatus for navigation system for route guiding to the destination, and more particularly, to a display method and apparatus which is capable of easily and quickly specifying a destination in the navigation system when using a xe2x80x9cPoint of Interest (POI)xe2x80x9d method by having a user pre-established set of POIs.
A vehicle navigation system performs vehicle travel guidance for enabling a driver to easily drive the vehicle to a selected destination. Such a navigation system detects the position of the vehicle, reads out map data pertaining to an area at the vehicle current position from a data storage medium, for example, a CD-ROM (compact disk read-only memory) or a DVD (digital versatile disc), and displays a map image on a monitor screen (display) while superposing a mark representing the current location of the vehicle on a predetermined portion of the map image.
The vehicle position is determined by a self-contained navigation sensors (e.g. a distance traveled sensor and a bearing sensor) mounted in the vehicle or by a global positioning system (GPS) including an artificial satellite (satellite navigation). The satellite enables absolute position detection and higher position accuracy than the self-contained navigation sensors. However, the satellite navigation involves problem of position detection failure such as in a tunnel or a building where the satellite radio signals are obstructed. Therefore, recent navigation systems utilize both self-contained navigation and satellite navigation to achieve improved performances.
As the present position of the vehicle changes with the travel of the vehicle, the vehicle current position mark in the map image on the screen is changed accordingly. Alternatively, the map is scrolled while the vehicle current position mark is fixed at a predetermined position, for example, at the center of the image. In either methods, the navigation system enables the driver to recognize the map information of the area at the vehicle position at a glance.
When a destination is not set, such a navigation system functions as a locator map which indicates the current location of the vehicle on a map image. When the destination is set, the navigation system starts a route guidance function for setting a guided route from the starting point to the destination. Typically, the route guidance function performs an intersection guidance process in which a monitor screen displays an enlarged intersection diagram and the direction in which the vehicle is to travel while displaying the guide route on a map. When a destination is input, a CPU in the navigation system determines a most suitable guided route from the current vehicle position to the destination and successively stores nodes (expressed in longitude and latitude) constituting the guided route in a memory.
During actual traveling, the node series stored in the memory is searched for a portion of the guided route to be displayed in a map display area of the monitor screen, and the portion of the guided route is highlighted so as to be discriminable from other routes. When the vehicle is within a predetermined distance of an intersection it is approaching, an intersection guidance diagram (an enlarged or highlighted intersection diagram with an arrow indicating the direction in which the vehicle is to turn at the intersection) is displayed to inform a driver of the desired one of roads or directions selectable at the intersection.
FIG. 1A shows an example of a locator map display containing a vehicle current position mark VCP on a map image 21. Typically, a navigation system shows the street on which the vehicle is running in the map image 21 and a name of the street such as xe2x80x9cW 190TH STxe2x80x9d in an information box 23 on the monitor screen. Other information such as a north pointer NP, a map scale and a current time may also be illustrated on the display screen. In this manner, the locator map display shows the current position of the vehicle on the map image, however, it does not perform the route guidance function because the destination is not set in the navigation system.
FIG. 1B shows an example of route guidance display which performs the route guidance function. The route guidance display is activated after specifying the destination. In addition to the map image 21 similar to the locator map of FIG. 1A, this example further shows an arrow indicating the direction (left) in which the vehicle is to turn at the intersection in a guidance information box 22 at the top of the screen. The guidance information box 22 also shows a name of the street xe2x80x9cPRAIRIE AVExe2x80x9d which intersects with the current street xe2x80x9cW 190TH STxe2x80x9d and a distance to the intersection. Thus, the navigation system indicates that the vehicle should make a left turn at the intersection with xe2x80x9cPRAIRIE AVExe2x80x9d.
Typically, the current street xe2x80x9cW 190TH STxe2x80x9d and the left side of the street xe2x80x9cPRAIRIE AVExe2x80x9d will be highlighted in the map image 21. Further, such route guidance is accompanied by voice instructions. If the direction of travel in the next intersection is left, the navigation system gives spoken guidance such as xe2x80x9cturn left at the next intersectionxe2x80x9d. In this example, an information box 24 at the bottom of the display screen includes information regarding the remaining distance to the final destination and an estimated time to reach the final destination.
In order to be guided by the route guidance mode such as shown in FIG. 1B, a destination must be specified in the navigation system so that the system can find one or more routes to get to the destination. Navigation systems today provide a variety of ways to specify the destination. A brief example of process for specifying the destination is shown in FIGS. 2A-2C.
By operating a menu key, a main menu screen 25 such as shown in FIG. 2A is displayed on the navigation system and a menu item xe2x80x9cDestinationxe2x80x9d is selected from the main menu. This allows the navigation system to display an xe2x80x9cEnter Destination byxe2x80x9d screen 27 as shown in FIG. 2B for specifying an input method for selecting the destination. The xe2x80x9cEnter Destination byxe2x80x9d screen 27 lists various methods for selecting the destination including xe2x80x9cAddressxe2x80x9d for specifying the city and address of the destination, xe2x80x9cIntersectionxe2x80x9d for specifying the names of two streets in the city which intersect with one another, and xe2x80x9cPoint of Interestxe2x80x9d for selecting the programmed destination based on the name, category or telephone number.
Other methods in the xe2x80x9cEnter Destination byxe2x80x9d screen 27 include xe2x80x9cRecent Routexe2x80x9d for specifying the destination based on the recent destinations saved in the navigation system, xe2x80x9cAddress Bookxe2x80x9d for selecting the address of the destination out of the addresses stored in the system, and xe2x80x9cMap Cursorxe2x80x9d for specifying the destination by pointing a cursor to the destination on the map. For example, the information in the address book is formed of a list of names and addresses of the places that a user frequently visits.
When selecting, for example, the xe2x80x9cAddressxe2x80x9d in FIG. 2B, the navigation system displays an xe2x80x9cEnter Street Namexe2x80x9d screen such as shown in FIG. 2F. The screen of FIG. 2F is basically a key board 38 for inputting the city and address in an address input box 37 on the monitor screen. The user inputs the street name and number in the address input box 37 through the key board 38.
After inputting the destination, the navigation system determines a route to the destination based on, for example, the shortest way to reach the destination, the route using many free ways as possible or the route without using toll road, and the like. Thus, the navigation system moves to the route guidance display such as shown in FIG. 1B which performs the route guidance.
This invention is directed to a display method and apparatus for a navigation system using the input method of xe2x80x9cPoint of Interestxe2x80x9d noted above. Although the xe2x80x9cPoint of Interestxe2x80x9d process is convenient and useful, because the recent storage medium provides a large volume of data involving this input method, it requires relatively many steps to finalize inputting the destination. Typically, the process of specifying a destination through the xe2x80x9cPoint of Interestxe2x80x9d is carried out in the following manner with reference to FIGS. 3A-3F.
In the example of FIGS. 3A-3F, it is assumed that an intended destination is a Japanese restaurant xe2x80x9cTaikoxe2x80x9d in Irvine, Calif. FIG. 3A shows an example of screen listing the various input methods noted above for selecting the destination. As shown in this example, typically, the navigation display lists several items, such as up to seven or eight items per page as a maximum number. Therefore, when the number of items exceeds the maximum number, it is usually necessary to scroll the display to see the other items outside of the current screen.
In FIG. 3A, by selecting the xe2x80x9cPoint of Interestxe2x80x9d and hitting an enter key, the navigation system displays a screen shown in FIG. 3B for finding the point of interest by either place names or place types. As shown in this example, this screen typically lists only two items. In FIG. 3B, by selecting the xe2x80x9cPlace Typexe2x80x9d and pressing the enter key, the navigation system displays a screen shown in FIG. 3C for selecting the categories of the point of interest. This screen lists various different categories of point of interest such as xe2x80x9cATMxe2x80x9d, xe2x80x9cAutomotivexe2x80x9d, xe2x80x9cBankxe2x80x9d, xe2x80x9cRestaurantxe2x80x9d, xe2x80x9cHotelxe2x80x9d, xe2x80x9cShoppingxe2x80x9d and others. Typically, the number of such categories are as many as forty or more. Therefore, in many cases, such a category list must be scrolled to find a favorite place type on the screen.
By selecting the category type xe2x80x9cRestaurantxe2x80x9d in FIG. 3C, the navigation system displays another category select screen listing sub-categories of the selected category. In this case, the sub-category screen shows types of food such as xe2x80x9cAmericanxe2x80x9d, xe2x80x9cCalifornianxe2x80x9d, xe2x80x9cChinesexe2x80x9d, xe2x80x9cFrenchxe2x80x9d, xe2x80x9cItalianxe2x80x9d, xe2x80x9cJapanesexe2x80x9d, xe2x80x9cKoreanxe2x80x9dand etc. Sometimes, such a sub-category list extends to several pages, requiring page scrolling to find a favorite sub-category.
By selecting the sub-category xe2x80x9cJapanesexe2x80x9d and pressing the enter key in FIG. 3D, the navigation system displays a screen for selecting a method of finding the places as shown in FIG. 3E. In this example, the methods include xe2x80x9cSort by Distancexe2x80x9d, xe2x80x9cNamexe2x80x9d and xe2x80x9cWithin a cityxe2x80x9d. The xe2x80x9cSort by Distancexe2x80x9d method is to find the places, Japanese restaurants, in this case, in the order of distance from the vehicle current position. The xe2x80x9cNamexe2x80x9d method is to find the places by inputting the name of the Japanese restaurant through, for example, a key board. The xe2x80x9cWithin a Cityxe2x80x9d method is to list the places, i.e., Japanese restaurants, within the city where the vehicle is located.
By selecting the xe2x80x9cSort by Distancexe2x80x9d and hitting the enter key in FIG. 3E, the navigation system displays a list of Japanese restaurants in the order of distance from the current vehicle position as shown in FIG. 3F. The screen of FIG. 3F is to select one of the names in the list. In the case where two or more restaurants having the same name exist, such restaurants will be listed in the order of the distance from the vehicle position.
The user selects the name xe2x80x9cTaikoxe2x80x9d in FIG. 3F and presses the enter key. Then, the navigation system displays a confirmation route screen such as shown in FIG. 3G for confirming the destination. The screen of FIG. 3G shows the name, address and phone number of the selected destination. Although not shown in the example of FIG. 3G, such a confirmation screen may also show a distance to the destination, an anticipated time length to reach the destination, and a direction to the destination.
By selecting xe2x80x9cOK to Proceedxe2x80x9d in FIG. 3G, the navigation system calculates the optimum route to the destination in FIG. 3H. The navigation system determines the route to the destination based on, for example, the shortest way to reach the destination, the route using many freeways as possible or the route without using toll road, and the like. During this process, the navigation system shows a progress of calculation by a bar graph as shown in the lower part of FIG. 3H. Then, the navigation system moves to the route guidance display such as shown in FIG. 1B which performs the route guidance.
As described in the foregoing, the process of specifying the destination by the xe2x80x9cPoint of Interestxe2x80x9d requires many steps of key operation. Especially, the category list includes a large number of POI categories and sub-categories, or even sub-categories of the sub-category, which requires to scroll the category screen to locate the intended category. Thus, the search method of xe2x80x9cPoint of Interestxe2x80x9d requires a relatively long time to finally specifying the destination, which may adversely affect the safe driving. Therefore, there is a need for a navigation system which can easily and quickly specify the destination through the xe2x80x9cPoint of Interestxe2x80x9d method.
It is, therefore, an object of the present invention to provide a navigation system which enables a user to easily and quickly specifies a destination in the navigation system when using a xe2x80x9cPoint of Interestxe2x80x9d method.
In this invention, the navigation system is designed to enable a user to quickly select a destination through a POI (Point of Interest) method by having a pre-established set of POIs, i.e., xe2x80x9cFavorite POIxe2x80x9d. Namely, the navigation system includes a new menu item xe2x80x9cFavorite POIxe2x80x9d for short cutting the process of selecting the category and sub-category of the intended destination. After selecting the input method xe2x80x9cPoint of Interestxe2x80x9d, the navigation system displays the xe2x80x9cFavorite POIxe2x80x9d menu along with other traditional menus. When selecting the xe2x80x9cFavorite POIxe2x80x9d, the navigation system displays a predetermined number of POIs which are pre-registered manually by a user or automatically by the navigation system.
More specifically, the method of the present invention includes the steps of: forming a set of points of interest (POI) listing a predetermined number of POIs (Favorite POI) selected based on user""s preference or automatically by the navigation system based on a predetermined rule; displaying a list of destination input methods and selecting a xe2x80x9cPoint of Interestxe2x80x9d menu; displaying a xe2x80x9cPoint of Interestxe2x80x9d screen for selecting a method of searching a point of interest wherein the xe2x80x9cPoint of Interestxe2x80x9d screen includes a xe2x80x9cFavorite POIxe2x80x9d menu; selecting the xe2x80x9cFavorite POIxe2x80x9d menu and displaying the list of predetermined number of xe2x80x9cFavorite POIxe2x80x9d for selecting a category of POI; and selecting one of the categories of POI in the xe2x80x9cFavorite POIxe2x80x9d and specifying a destination in the selected category of the xe2x80x9cFavorite POIxe2x80x9d.
Each of the POIs in the list of xe2x80x9cFavorite POIxe2x80x9d indicates a category or a combination of a category and sub-category of the selected POI. The step of forming the xe2x80x9cFavorite POIxe2x80x9d includes a step of selecting a category or a combination of higher category and lower category of POI preferred by a user through a system setup process provided in the navigation system.
The predetermined rule for automatically forming the list of xe2x80x9cFavorite POIxe2x80x9d by the navigation system is an order of frequent use of same POI or an order of recent use of POIs. Alternatively, in the step of forming the list of POIs, the list is automatically determined by the navigation system based on an order of most recently used POIs (xe2x80x9cLast POIxe2x80x9d).
The display method further includes a step of confirming the selected destination by displaying detailed information on the selected destination. The display method further includes a step of determining an appropriate route to the selected destination and displaying a route guidance screen for guiding a user to reach the selected destination.
Another aspect of the present invention is a display apparatus for a vehicle navigation system. The display apparatus is configured by various means for achieving the display methods described above which utilizes the list of xe2x80x9cFavorite POIxe2x80x9d menu and/or xe2x80x9cLast POIxe2x80x9d menu.
According to the present invention, the vehicle navigation system enables the user to enter the destination easily and quickly through the xe2x80x9cPoint of Interestxe2x80x9d input method. First, the user selects the xe2x80x9cPoint of Interestxe2x80x9d input method, then selects the xe2x80x9cFavorite POIxe2x80x9d or xe2x80x9cLast POIxe2x80x9d which causes to display pre-established list of POIs. Since this process does not require a long list of category and sub-category or page scrolling of the category or sub-category list, the user can easily and quickly specify the destination in the navigation system.